Treponema pallidum p47

Treponema pallidum is a spirochaete bacterium with subspecies that cause treponemal diseases such as syphilis, bejel, pinta, and yaws. The treponemes have a cytoplasmic and an outer membrane. Using light microscopy, treponemes are only visible using dark field illumination.

Treponema pallidum p47 is a major outer membrane protein of Treponema pallidum, the pathogen responsible for syphilis. Its primary biological function is to mediate the bacterium's adhesion to host cells, which is critical for establishing infection after transmission (e.g., via sexual contact). Without this adhesion, Treponema pallidum cannot attach to mucosal tissues and would be cleared by the host's natural defenses. P47 is also one of the most immunogenic proteins of Treponema pallidum, meaning it triggers a strong antibody response in infected people. These antibodies are used in diagnostic tests to identify syphilis, as they are present in all stages of the disease (except very early primary syphilis). Due to its role in adhesion and its immunogenicity, p47 is a key target for syphilis vaccine development. A vaccine that induces anti-p47 antibodies could prevent Treponema pallidum from adhering to host cells, stopping infection before it progresses to symptoms. This makes p47 a vital molecule for both syphilis diagnosis and prevention efforts.